New compounds of the benzanthraquinone series



Patented Dec. 22, 1931 um-D "STATES PATENT OFFICE RUDOLF M. HEIDENREICH, OF ELBERI ELD, GERMANY, ASSIGNOR T GENERAL ANILINE W'ORKS, INQ, OF NEW YORK, N. Y. A CORPORATION OF DELAWARE 7 NEW COMPOUNDS OF THE BENZANTHRAQUINONE SERIES No Drawing. Application filed July 30, 1928, Serial No. 296,412, and in Germany October 23, 1926.

My present invention relates to newcompounds of the benzanthraquinone serles,v

more particularly to compounds of the following general formula ao at a 5 wherein R stands for hydrogen, alkyl, aralkyl or aryl. In the'above indicated formula the nuclear hydrogen atoms may be substituted.

I have found that my suitably heating 1.8- naphthalimide -4i-benzoyl ortho carhoxylic acid with strong sulfuric acid it can be transformed into the corresponding benzanthraquinone compound, namely 1.2-benzanthraquinone-peri-dicarboxylic acid imide, without an'ess ential p art of thenaph th alimide compound being splitvup with the formation of the corresponding dicarboxylic acid or dicarboxylic anhydride. This new observation shows that the formation of the benzanthraquinone ring precedes the splitting up of the naphthalimide ring and it involves the valuable technical advantage that comparatively complicated compounds of the benzanthraquinone series can be prepared by practically very simple and cheap methods.

A behaviour which is quite analogous to that 1.8-naphthalimide-i-beiiZoyl-ortliocarboxylic acid show the corresponding alkylimides, aralkylimides and arylimides, that is to say the reaction products of 1.8-naphthalic-anhydridel-benzoyl-orth0 carboxylic acid and their derivatives with primary aliphatic, aliphatic-aromatic or aromatic monoamines.

Generally speaking according to this invention products are obtained which are characterized by the followlng general formula:

wherein it 'stands, for hydrogen, alkyl, aralkyl or aryl. In the above indicated formula the nuclear hydrogen atoms may be substituted. i

The benzanthraquinone compounds which can be prepared in the above described simple manner are Valuable yellow to orange vat dyestuifs. Their shades range from yellow to orange in case the nuclear hydrogen atoms are not substituted or substituted by sub stituents not considerably deepening the color of anthraquinone dyestuffs, such as chlorine or bromine, whereas when introducing other substituents, such as amino groups, into the molecule dyestuffs dyeing-red or even violet shades may be obtained.

The followingexamples are given by way of illustration, it being understood that they are inno way limitative, the parts being by weight Example J.34.5 parts of 1.8-naphthalimideA-benZoyl-Orthocarboxylic acid, prepared from 1.8-naphthalic anhydridel-benzoyl-ortho-carboxylic acid by heating with ammonia, are introduced into ab-out 150 parts of concentrated sulfuric acid and heated for some to minutes from C. to 1T0 C. rlfter pouring the sulfuric acid solution into a large amount of cold water the yellow precipitate is filtered, washed until neutral-and the residue is extracted with dilute alkali, repeating this if necessary. There remains the beautifulyellow colored 1.2-benzanthraquinone-peri-dicarboxylic acid imide of the probable formula which forms a bluish green vat with alkali and hydrosulfite and can be recrystallized from high boiling organic solvents; the melting point is above 300 C. I

Ewample 2.35.9 parts of 1.8-naphthal- (N methyl) -imidell benzoyl -ortho-carboxylic acid are heated for some 10 to 15 minutes from about 1609C. to 170C. in about 150 parts of concentrated sulfuric acid; the resulting 1.2-benzanthraquinone-peri-dicarboxylic acid (N-rnethyl) imide is isolated and purified as described in the preceding example. It represents a yellow product which forms an olive colored vat and melts at 280 C. It has the probable constitution carboxylic acid is used, the corresponding 1.2

benzanthraquinone peri --dicarboxylic acid- (N-aryl)-imides are obtainable in a similar manner, in consequence of the ring formation by means of concentrated sulfuric acid.

In a quite analogous manner the products of interaction from the derivatives of 1. 8 -naphthalic anhydride-4-benzoyl-ortho-carboxylic acid with ammonia, primary aliphatic, aliphatic-aromatic or aromatic monoamines can be transformed into the corresponding benzanthraquinone derivatives in strong sulfurlc acid solution at elevated temperature.

In all examples the reaction temperature may vary between about 150200 C.

probable general formula:

wherein R stands for hydrogemalkyl, aralkyl or aryl, said products being yellow to orange vat dyestuffs of good fastness properties.

2. As new products, the compounds of the 5 following general formula wherein R-stands for hydrogen or methyl,

' said products being yellow to orange Vat dyestufis of valuable fastness properties.

In testimony whereof I have hereunto set my hand.

RUDOLF M. HEIDENREICH. [1,. s.] 

